Silver Bullet throttle body spacers create turbulence in the air flow at the point just prior entry into the engine increasing horsepower, torque and improving throttle response and fuel efficiency. Silver Bullet throttle body spacers are constructed out of durable T-6061 billet aluminum and using a unique serrated/helix entry to create turbulence at the manifold while eliminating the annoying whistle found in other helix only throttle spacers. PartNumber : afe46-33005 Description : Silver Bullet Throttle Body Spacer 2004 Ford F-250 Super Duty Harley-Davidson Edition V10.-cc Air Intake Systems::Throttle Body Spacers 2004 Ford F-250 Super Duty King Ranch V10.-cc Air Intake Systems::Throttle Body Spacers 1999-2004 Ford F-250 Super Duty Lariat V10.-cc Air Intake Systems::Throttle Body Spacers 1999-2004 Ford F-250 Super Duty XL V10.-cc Air Intake Systems::Throttle Body Spacers 1999-2004 Ford F-250 Super Duty XLT V10.-cc Air Intake Systems::Throttle Body Spacers 2004 Ford F-350 Super Duty Harley-Davidson Edition V10.-cc Air Intake Systems::Throttle Body Spacers 2003-2004 Ford F-350 Super Duty King Ranch V10.-cc Air Intake Systems::Throttle Body Spacers 1999-2004 Ford F-350 Super Duty Lariat V10.-cc Air Intake Systems::Throttle Body Spacers 1999-2004 Ford F-350 Super Duty XL V10.-cc Air Intake Systems::Throttle Body Spacers 1999-2004 Ford F-350 Super Duty XLT V10.-cc Air Intake Systems::Throttle Body Spacers